# Phase transitions in filtration of Redlich-Kwong gases

## TL;DR

This paper investigates phase transitions in the filtration of Redlich-Kwong gases by analyzing thermodynamical states as geometric structures and linking singularities to phase changes, providing explicit solutions and phase distributions.

## Contribution

It introduces a geometric framework for understanding phase transitions in real gases described by Redlich-Kwong equations, connecting singularities to physical phenomena.

## Key findings

- Singularities of thermodynamic state projections relate to phase transitions.
- Explicit formulas for boundary problems are derived.
- Distribution of phases in space is characterized.

## Abstract

In this paper we study a 3-dimensional filtration of real gases described by Redlich-Kwong equations of state. Thermodynamical states are considered as Legendrian (Lagrangian) submanifolds in contact (symplectic) space. Connection between singularities of their projection on the space of intensive variables and phase transitions is shown. Explicit formulae for the Dirichlet boundary problem are given and the distribution of phases in space is shown.